The present invention relates to a composition for the oxidation dyeing of keratin fibres, in particular human keratin fibres such as the hair, comprising at least one oxidation base chosen from diaminopyrazoles and triaminopyrazoles, in combination with at least one meta-aminophenol which is halogenated ortho to the phenol, as coupler, and to the dyeing process using this composition with an oxidizing agent.
It is known practice to dye keratin fibres, and in particular human hair, with dye compositions containing oxidation dye precursors, in particular ortho- or para-phenylenediamines, ortho- or para-aminophenols or heterocyclic compounds such as pyrazole derivatives, which are generally referred to as oxidation bases. Oxidation dye precursors, or oxidation bases, are colourless or weakly coloured compounds which, when combined with oxidizing products, can give rise to coloured compounds and dyes by means of a process of oxidative condensation.
It is also known that the shades obtained with oxidation bases can be varied by combining them with suitably selected couplers or coloration modifiers, the latter possibly being chosen in particular from aromatic meta-diamines, meta-aminophenols, meta-diphenols and certain heterocyclic compounds.
The variety of molecules used as oxidation bases and couplers allows a wide range of colours to be obtained.
The so-called xe2x80x9cpermanentxe2x80x9d coloration obtained by means of these oxidation dyes must moreover satisfy a certain number of requirements. Thus, it must have no toxicological drawbacks, it must allow shades to be obtained in the desired intensity and it must satisfactorily withstand external agents (light, bad weather, washing, permanent-waving, perspiration or rubbing).
The dyes must also be able to cover white hair, and, lastly, they must be as unselective as possible, i.e. they must allow only the smallest possible differences in colour along the same keratin fibre, which may in fact be differently sensitized (i.e. damaged) between its tip and its root.
Compositions for the oxidation dyeing of keratin fibres, containing pyrazole derivatives such as 4,5-diaminopyrazoles, 3,4-diaminopyrazoles or 3,4,5-triaminopyrazoles as oxidation base, in combination with couplers conventionally used for oxidation dyeing, such as, for example, meta-phenylenediamines, meta-aminophenols, meta-diphenols and heterocyclic couplers such as, for example, indole derivatives, have already been proposed, in particular in German patent applications DE 3 843 892, DE 4 234 887, DE 4 234 886, DE 4 234 885 and DE 195 43 988. However, such compositions are not entirely satisfactory, in particular as regards the fastness of the colorations obtained with regard to the various attacking factors to which the hair may be subjected, and in particular with regard to perspiration.
However, the Applicant has now discovered that it is possible to obtain novel powerful dyes that are particularly resistant to the various attacking factors to which the hair may be subjected, by combining, as oxidation base, at least one diaminopyrazole and/or at least one triaminopyrazole and, as coupler, a meta-aminophenol halogenated in a position ortho to the phenol.
This discovery forms the basis of the present invention.
A first subject of the invention is thus a composition for the oxidation dyeing of keratin fibres and in particular human keratin fibres such as the hair, characterized in that it comprises, in a medium which is suitable for dyeing:
at least one oxidation base chosen from diaminopyrazoles and triaminopyrazoles;
and at least one coupler chosen from the halogenated meta-aminophenols of formula (I) below, and the addition salts thereof with an acid: 
in which:
R1 and R2, which may be identical or different, represent a hydrogen atom, a halogen atom such as chlorine, bromine, iodine or fluorine, a C1-C4 alkyl radical, a C1-C4 monohydroxyalkyl radical, a C2-C4 polyhydroxyalkyl radical, a C1-C4 alkoxy radical, a C1-C4 monohydroxyalkoxy radical or a C2-C4 polyhydroxyalkoxy radical;
R3 and R4, which may be identical or different, represent a hydrogen atom, a C1-C4 alkyl radical, a C1-C4 monohydroxyalkyl radical, a C2-C4 polyhydroxyalkyl radical or a C1-C4 monoaminoalkyl radical; it being understood that at least one of the radicals R1 and R2 represents a halogen atom.
The oxidation dye composition in accordance with the invention makes it possible to obtain intense colorations in varied shades, which are relatively unselective and which have excellent properties of resistance both with respect to atmospheric agents such as light and bad weather, and with respect to perspiration and the various treatments to which the hair may be subjected (shampooing, permanent-waving). These properties are particularly noteworthy especially as regards the resistance of the colorations with respect to perspiration.
Among the C1-C4 alkyl and C1-C4 alkoxy radicals of the compounds of formula (I) above, mention may be made in particular of the methyl, ethyl, propyl, methoxy and ethoxy radicals.
Among the halogenated meta-aminophenols of formula (I), mention may be made more particularly of 3-amino-6-chlorophenol, 3-amino-6-bromophenol, 3-(xcex2-aminoethyl)amino-6-chlorophenol, 3-(xcex2-hydroxyethyl)-amino-6-chlorophenol and 3-amino-2-chloro-6-methylphenol, and the addition salts thereof with an acid.
Among the diaminopyrazoles which can be used as oxidation bases in the dye compositions in accordance with the invention, mention may be made more particularly of:
a) the diaminopyrazoles of formula (II) below, and the addition salts thereof with an acid: 
in which:
R5 represents a hydrogen atom, a C1-C6 alkyl radical, a C2-C4 hydroxyalkyl radical, a benzyl radical, a phenyl radical, a benzyl radical substituted with a halogen atom or with a C1-C4 alkyl or C1-C4 alkoxy group, or forms, with the nitrogen atom of the group NR7R8 in position 5, a hexahydropyridazine or tetrahydropyrazole heterocycle which is optionally monosubstituted with a C1-C4 alkyl group;
R6 and R7 which may be identical or different, represent a hydrogen atom, a C1-C4 alkyl radical, a C2-C4 hydroxyalkyl radical, a benzyliradical or a phenyl radical;
R8 represents a hydrogen atom, or a C1-C6 alkyl or C2-C4 hydroxyalkyl radical; with the proviso that R6 represents a hydrogen atom when R5 represents a substituted benzyl radical or forms a heterocycle with the nitrogen atom of the group NR7R8 in position 5;
b) the diaminopyrazoles of formula (III) below, and the addition salts thereof with an acid: 
in which:
R9, R10, R11, R12 and R13, which may be identical or different, represent a hydrogen atom; a linear or branched C1-C6 alkyl radical; a C2-C4 hydroxyalkyl radical; a C2-C4 aminoalkyl radical; a phenyl radical; a phenyl radical substituted with a halogen atom or a C1-C4 alkyl, C1-C4 alkoxy, nitro, trifluoromethyl, amino or C1-C4 alkylamino radical; a benzyl radical; a benzyl radical substituted with a halogen atom or with a C1-C4 alkyl, C1-C4 alkoxy, methylenedioxy or amino radical; or a radical 
in which m and n are integers, which may be identical or different, between 1 and 3 inclusive, X represents an oxygen atom or an NH group, Y represents a hydrogen atom or a methyl radical, and Z represents a methyl radical, a group OR or NRRxe2x80x2 in which R and Rxe2x80x2, which may be identical or different, denote a hydrogen atom, a methyl radical or an ethyl radical, it being understood that when R10 represents a hydrogen atom, then R11 can also represent an amino or C1-C4 alkylamino radical,
R14 represents a linear or branched C1-C6 alkyl radical; a C1-C4 hydroxyalkyl radical; a C1-C4 aminoalkyl radical; a (C1-C4)alkylamino(C1-C4)alkyl radical; a di(C1-C4)alkylamino(C1-C4)alkyl radical; a hydroxy(C1-C4)alkylamino(C1-C4)alkyl radical; a (C1-C4)alkoxymethyl radical; a phenyl radical; a phenyl radical substituted with a halogen atom or with a C1-C4 alkyl, C1-C4 alkoxy, nitro, trifluoromethyl, amino or C1-C4 alkylamino radical; a benzyl radical; a benzyl radical substituted with a halogen atom or with a C1-C4 alkyl, C1-C4 alkoxy, nitro, trifluoromethyl, amino or C1-C4 alkylamino radical; a heterocycle chosen from thiophene, furan and pyridine, or alternatively a radical xe2x80x94(CH2)pxe2x80x94Oxe2x80x94(CH2)qxe2x80x94ORxe2x80x3, in which p and q are integers, which may be identical or different, between 1 and 3 inclusive, and Rxe2x80x3 represents a hydrogen atom or a methyl radical, it being understood that, in formula (III) above,
at least one of the radicals R10, R11, R12 and R13 represents a hydrogen atom,
when R10, or R12, respectively, represents a substituted or unsubstituted phenyl radical, or a benzyl radical or a radical 
then R11, or R13, respectively, cannot represent any of these three radicals,
when R12 and R13 simultaneously represent a hydrogen atom, then R9 can form, with R10 and R11, a hexahydropyrimidine or tetrahydroimidazole heterocycle which is optionally substituted with a C1-C4 alkyl or 1,2,4-tetrazole radical,
when R10, R11, R12 and R13 represent a hydrogen atom or a C1-C6 alkyl radical, then R9 or R14 can also represent a 2-, 3- or 4-pyridyl, 2- or 3-thienyl or 2- or 3-furyl heterocyclic residue which is optionally substituted with a methyl radical or alternatively a cyclohexyl radical.
Among the triaminopyrazoles which can be used as oxidation bases in the dye compositions in accordance with the invention, mention may be made more particularly of the compounds of formula (IV) below, and the addition salts thereof with an acid: 
in which:
R15 and R16, which may be identical or different, represent a hydrogen atom or a C1-C4 alkyl or C2-C4 hydroxyalkyl radical.
Among the diaminopyrazoles of formula (II) above, mention may be made more particularly of 4,5-diamino-1-(4xe2x80x2-methoxybenzyl)pyrazole, 4,5-diamino-1-(4xe2x80x2-methylbenzyl)pyrazole, 4,5-diamino-1-(4xe2x80x2-chlorobenzyl)pyrazole, 4,5-diamino-1-(3xe2x80x2-methoxybenzyl)pyrazole, 4-amino-1-(4xe2x80x2-methoxybenzyl)-5-methylaminopyrazole, 4-amino-5-(xcex2-hydroxyethyl)amino-1-(4xe2x80x2-methoxybenzyl)pyrazole, 4-amino-5-(xcex2-hydroxyethyl)amino-1-methylpyrazole, 4-amino-(3)5-methylaminopyrazole, 3-(5)4-diaminopyrazole, 4,5-diamino-1-methylpyrazole, 4,5-diamino-1-benzylpyrazole, 3-amino-4,5,7,8-tetrahydropyrazolo[1,5-a]pyrimidine, 7-amino-2,3-dihydro-1H-imidazolo[1,2-b]pyrazole and 3-amino-8-methyl-4,5,7,8-tetrahydropyrazolo[1,5-a]pyrimidine, and the addition salts thereof with an acid.
The diaminopyrazoles of formula (III) are known compounds which can be prepared according to the synthetic process as described, for example, in French patent application FR-A-2 733 749.
Among the diaminopyrazoles of formula (III) above, mention may be made more particularly of:
1-benzyl-4,5-diamino-3-methylpyrazole,
4,5-diamino-1-(xcex2-hydroxyethyl)-3-(4xe2x80x2-methoxyphenyl)-pyrazole,
4,5-diamino-1-(xcex2-hydroxyethyl)-3-(4xe2x80x2-methylphenyl)-pyrazole,
4,5-diamino-1-(xcex2-hydroxyethyl)-3-(3xe2x80x2-methyiphenyl)-pyrazole,
4,5-diamino-3-methyl-1-isopropylpyrazole,
4,5-diamino-3-(4xe2x80x2-methoxyphenyl)-1-isopropylpyrazole,
4,5-diamino-1-ethyl-3-methylpyrazole,
4,5-diamino-1-ethyl-3-(4xe2x80x2-methoxyphenyl)pyrazole,
4,5-diamino-3-hydroxymethyl-1-methylpyrazole,
4,5-diamino-1-ethyl-3-hydroxymethylpyrazole,
4,5-diamino-3-hydroxymethyl-1-isopropylpyrazole,
4,5-diamino-3-hydroxymethyl-1-tert-butylpyrazole,
4,5-diamino-3-hydroxymethyl-1-phenylpyrazole,
4,5-diamino-3-hydroxymethyl-1-(2xe2x80x2-methoxyphenyl)-pyrazole,
4,5-diamino-3-hydroxymethyl-1-(3xe2x80x2-methoxyphenyl)-pyrazole,
4,5-diamino-3-hydroxymethyl-1-(4xe2x80x2-methoxyphenyl)-pyrazole,
1-benzyl-4,5-diamino-3-hydroxymethylpyrazole,
4,5-diamino-3-methyl-1-(2xe2x80x2-methoxyphenyl)pyrazole,
4,5-diamino-3-methyl-1-(3xe2x80x2-methoxyphenyl)pyrazole,
4,5-diamino-3-methyl-1-(4xe2x80x2-methoxyphenyl)pyrazole,
3-aminomethyl-4,5-diamino-1-methylpyrazole,
3-aminomethyl-4,5-diamino-1-ethylpyrazole,
3-aminomethyl-4,5-diamino-1-isopropylpyrazole,
3-aminomethyl-4,5-diamino-1-tert-butylpyrazole,
4,5-diamino-3-dimethylaminomethyl-1-methylpyrazole,
4,5-diamino-3-dimethylaminomethyl-1-ethylpyrazole,
4,5-diamino-3-dimethylaminomethyl-1-isopropylpyrazole,
4,5-diamino-3-dimethylaminomethyl-1-tert-butylpyrazole,
4,5-diamino-3-ethylaminomethyl-1-methylpyrazole,
4,5-diamino-3-ethylaminomethyl-1-ethylpyrazole,
4,5-diamino-3-ethylaminomethyl-1-isopropylpyrazole,
4,5-diamino-3-ethylaminomethyl-1-tert-butylpyrazole,
4,5-diamino-3-methylaminomethyl-1-methylpyrazole,
4,5-diamino-3-methylaminomethyl-1-isopropylpyrazole,
4,5-diamino-1-ethyl-3-methylaminomethylpyrazole,
1-tert-butyl-4,5-diamino-3-methylaminomethylpyrazole,
4,5-diamino-3-[(xcex2-hydroxyethyl)aminomethyl]-1-methylpyrazole,
4,5-diamino-3-[(xcex2-hydroxyethyl)aminomethyl]-1-isopropylpyrazole,
4,5-diamino-1-ethyl-3-[(xcex2-hydroxyethyl)aminomethyl]-pyrazole,
1-tert-butyl-4,5-diamino-3-[(xcex2-hydroxyethyl)-aminomethyl]pyrazole,
4-amino-5-(xcex2-hydroxyethyl)amino-1,3-dimethylpyrazole,
4-amino-5-(xcex2-hydroxyethyl)amino-1-isopropyl-3-methylpyrazole,
4-amino-5-(xcex2-hydroxyethyl)amino-1-ethyl-3-methylpyrazole,
4-amino-5-(xcex2-hydroxyethyl)amino-1-tert-butyl-3-methylpyrazole,
4-amino-5-(xcex2-hydroxyethyl)amino-1-phenyl-3-methylpyrazole,
4-amino-5-(xcex2-hydroxyethyl)amino-1-(2-methoxyphenyl)-3-methylpyrazole,
4-amino-5-(xcex2-hydroxyethyl)amino-1-(3-methoxyphenyl)-3-methylpyrazole,
4-amino-5-(xcex2-hydroxyethyl)amino-1-(4-methoxyphenyl)-3-methylpyrazole,
4-amino-5-(xcex2-hydroxyethyl)amino-1-benzyl-3-methylpyrazole,
4-amino-1-ethyl-3-methyl-5-methylaminopyrazole,
4-amino-1-tert-butyl-3-methyl-5-methylaminopyrazole,
4,5-diamino-1,3-dimethylpyrazole,
4,5-diamino-3-tert-butyl-1-methylpyrazole,
4,5-diamino-1-tert-butyl-3-methylpyrazole,
4,5-diamino-1-methyl-3-phenylpyrazole,
4,5-diamino-1-(xcex2-hydroxyethyl)-3-methylpyrazole,
4,5-diamino-1-(xcex2-hydroxyethyl)-3-phenylpyrazole,
4,5-diamino-1-methyl-3-(2xe2x80x2-chlorophenyl)pyrazole,
4,5-diamino-1-methyl-3-(4xe2x80x2-chlorophenyl)pyrazole,
4,5-diamino-1-methyl-3-(3xe2x80x2-trifluoromethylphenyl)-pyrazole,
4,5-diamino-1,3-diphenylpyrazole,
4,5-diamino-3-methyl-1-phenylpyrazole,
4-amino-1,3-dimethyl-5-phenylaminopyrazole,
4-amino-1-ethyl-3-methyl-5-phenylaminopyrazole,
4-amino-1,3-dimethyl-5-methylaminopyrazole,
4-amino-3-methyl-1-isopropyl-5-methylaminopyrazole,
4-amino-3-isobutoxymethyl-1-methyl-5-methylaminopyrazole,
4-amino-3-methoxyethoxymethyl-1-methyl-5-methylaminopyrazole,
4-amino-3-hydroxymethyl-1-methyl-5-methylaminopyrazole,
4-amino-1,3-diphenyl-5-phenylaminopyrazole,
4-amino-3-methyl-5-methylamino-1-phenylpyrazole,
4-amino-1,3-dimethyl-5-hydrazinopyrazole,
5-amino-3-methyl-4-methylamino-1-phenylpyrazole,
5-amino-1-methyl-4-(N,N-methylphenyl)amino-3-(4xe2x80x2-chlorophenyl)pyrazole,
5-amino-3-ethyl-1-methyl-4-(N,N-methylphenyl)aminopyrazole,
5-amino-1-methyl-4-(N,N-methylphenyl)amino-3-phenylpyrazole,
5-amino-3-ethyl-4-(N,N-methylphenyl)aminopyrazole,
5-amino-4-(N,N-methylphenyl)amino-3-phenylpyrazole,
5-amino-4-(N,N-methylphenyl)amino-3-(4xe2x80x2-methylphenyl)pyrazole,
5-amino-3-(4xe2x80x2-chlorophenyl)-4-(N,N-methylphenyl)-aminopyrazole,
5-amino-3-(4xe2x80x2-methoxyphenyl)-4-(N,N-methylphenyl)-aminopyrazole,
4-amino-5-methylamino-3-phenylpyrazole,
4-amino-5-ethylamino-3-phenylpyrazole,
4-amino-5-ethylamino-3-(4xe2x80x2-methylphenyl)pyrazole,
4-amino-3-phenyl-5-propylaminopyrazole,
4-amino-5-butylamino-3-phenylpyrazole,
4-amino-3-phenyl-5-phenylaminopyrazole,
4-amino-5-benzylamino-3-phenylpyrazole,
4-amino-5-(4xe2x80x2-chlorophenyl)amino-3-phenylpyrazole,
4-amino-3-(4xe2x80x2-chlorophenyl)-5-phenylaminopyrazole,
4-amino-3-(4xe2x80x2-methoxyphenyl)-5-phenylaminopyrazole,
1-(4xe2x80x2-chlorobenzyl)-4,5-diamino-3-methylpyrazole,
4,5-diamino-3-hydroxymethyl-1-isopropylpyrazole,
4-amino-1-ethyl-3-methyl-5-methylaminopyrazole,
4-amino-5-(2xe2x80x2-aminoethyl)amino-1,3-dimethylpyrazole, and the addition salts thereof with an acid.
Among these diaminopyrazoles of formula (III) above, the ones more particularly preferred are:
4,5-diamino-1,3-dimethylpyrazole,
4,5-diamino-3-methyl-1-phenylpyrazole,
4,5-diamino-1-methyl-3-phenylpyrazole,
4-amino-1,3-dimethyl-5-hydrazinopyrazole,
1-benzyl-4,5-diamino-3-methylpyrazole,
4,5-diamino-3-tert-butyl-1-methylpyrazole,
4,5-diamino-1-tert-butyl-3-methylpyrazole,
4,5-diamino-1-(xcex2-hydroxyethyl)-3-methylpyrazole,
4,5-diamino-1-ethyl-3-methylpyrazole,
4,5-diamino-1-ethyl-3-(4xe2x80x2-methoxyphenyl)pyrazole,
4,5-diamino-1-ethyl-3-hydroxymethylpyrazole,
4,5-diamino-3-hydroxymethyl-1-methylpyrazole,
4,5-diamino-3-hydroxymethyl-1-isopropylpyrazole,
4,5-diamino-3-methyl-1-isopropylpyrazole,
4-amino-5-(2xe2x80x2-aminoethyl)amino-1,3-dimethylpyrazole, and the addition salts thereof with an acid.
Among the triaminopyrazoles of formula (IV) above, mention may be made more particularly of 3,4,5-triaminopyrazole, 1-methyl-3,4,5-triaminopyrazole, 3,5-diamino-1-methyl-4-methylaminopyrazole and 3,5-diamino-4-(xcex2-hydroxyethyl)amino-1-methylpyrazole, and the addition salts thereof with an acid.
The diaminopyrazole(s) and/or the triaminopyrazole(s) in accordance with the invention and/or the corresponding addition salt(s) with an acid preferably represent(s) from 0.0005 to 12% by weight approximately relative to the total weight of the dye composition, and even more preferably from 0.005 to 6% by weight approximately relative to this weight.
The halogenated meta-aminophenol(s) of formula (I) in accordance with the invention and/or the corresponding addition salt(s) with an acid preferably represent(s) from 0.0001 to 5% by weight approximately relative to the total weight of the dye composition, and even more preferably from 0.005 to 3% by weight approximately relative to this weight.
The dye compositions in accordance with the invention can contain other couplers conventionally used for oxidation dyeing, other than the halogenated meta-aminophenols of formula (I), and/or other oxidation bases conventionally used for oxidation dyeing, other than a diaminopyrazole and a triaminopyrazole and/or direct dyes, in particular in order to modify the shades or to enrich them with glints.
In general, the addition salts with an acid which can be used in the context of the dye compositions of the invention (oxidation bases and couplers) are chosen in particular from the hydrochlorides, hydrobromides, sulphates, tartrates, lactates and acetates.
The medium which is suitable for dyeing (or support) generally consists of water or of a mixture of water and at least one organic solvent to dissolve the compounds which would not be sufficiently soluble in water. Organic solvents which may be mentioned, for example, are C1-C4 lower alkanols, such as ethanol and isopropanol; glycerol; glycols and glycol ethers such as 2-butoxyethanol, propylene glycol, propylene glycol monomethyl ether, diethylene glycol monoethyl ether and monomethyl ether, as well as aromatic alcohols such as benzyl alcohol or phenoxyethanol, similar products and mixtures thereof.
The solvents can be present in proportions preferably of between 1 and 40% by weight approximately relative to the total weight of the dye composition, and even more preferably between 5 and 30% by weight approximately.
The pH of the dye composition in accordance with the invention is generally between 3 and 12 approximately and even more preferably between 5 and 11 approximately. It can be adjusted to the desired value by means of acidifying or basifying agents usually used in the dyeing of keratin fibres.
Among the acidifying agents which may be mentioned, for example, are inorganic or organic acids such as hydrochloric acid, orthophosphoric acid, carboxylic acids such as tartaric acid, citric acid and lactic acid, and sulphonic acids.
Among the basifying agents which may be mentioned, for example, are aqueous ammonia, alkaline carbonates, alkanolamines such as mono-, di- and triethanolamine and derivatives thereof, sodium hydroxide, potassium hydroxide and the compounds of formula (V) below: 
in which R is a propylene residue optionally substituted with a hydroxyl group or a C1-C4 alkyl radical; R17, R18, R19 and R20, which may be identical or different, represent a hydrogen atom or a C1-C4 alkyl or C1-C4 hydroxyalkyl radical.
The dye composition according to the invention can also contain various adjuvants conventionally used in compositions for dyeing the hair, such as anionic, cationic, nonionic, amphoteric or zwitterionic surfactants or mixtures thereof, anionic, cationic, nonionic, amphoteric or zwitterionic polymers or mixtures thereof, inorganic or organic thickeners, antioxidants, penetrating agents, sequestering agents, fragrances, buffers, dispersants, conditioners such as, for example, volatile or non-volatile, modified or unmodified silicones, film-forming agents, ceramides, preserving agents and opacifiers.
Needless to say, a person skilled in the art will take care to select this or these optional additional compound(s) such that the advantageous properties intrinsically associated with the combination in accordance with the invention are not, or are not substantially, adversely affected by the addition(s) envisaged.
The dye composition according to the invention can be in various forms, such as in the form of liquids, creams or gels or in any other form which is suitable for dyeing keratin fibres, and in particular human hair.
A subject of the invention is also a process for dyeing keratin fibres, and in particular human keratin fibres such as the hair, using the dye composition as defined above.
According to this process, the dye composition as defined above is applied to the fibres, the colour being developed at acidic, neutral or alkaline pH with the aid of an oxidizing agent which is added to the dye composition just at the time of use, or which is present in an oxidizing composition that is applied simultaneously or sequentially.
According to one particularly preferred embodiment of the dyeing process according to the invention, the dye composition described above is mixed, at the time of use, with an oxidizing composition containing, in a medium which is suitable for dyeing, at least one oxidizing agent present in an amount which is sufficient to develop a coloration. The mixture obtained is then applied to the keratin fibres and is left to stand on them for 3 to 60 minutes approximately, preferably 5 to 40 minutes approximately, after which the fibres are rinsed, washed with shampoo, rinsed again and dried.
The oxidizing agent present in the oxidizing composition as defined above can be chosen from the oxidizing agents conventionally used for the oxidation dyeing of keratin fibres, and among which mention may be made of hydrogen peroxide, urea peroxide, alkali metal bromates, persalts such as perborates, percarbonates and persulphates, and peracids. Hydrogen peroxide is particularly preferred.
The pH of the oxidizing composition containing the oxidizing agent as defined above is such that after mixing with the dye composition, the pH of the resulting composition applied to the keratin fibres preferably ranges between 3 and 12 approximately and even more preferably between 5 and 11. It is adjusted to the desired value by means of acidifying or basifying agents usually used in the dyeing of keratin fibres and as defined above.
The oxidizing composition as defined above can also contain various adjuvants conventionally used in compositions for dyeing the hair and as defined above.
The composition which is finally applied to the keratinfibres can be in various forms, such as in the form of liquids, creams or gels or in any other form which is suitable for dyeing keratin fibres, and in particular human hair.
Another subject of the invention is a multi-compartment dyeing device or xe2x80x9ckitxe2x80x9d or any other multi-compartment packaging system, a first compartment of which contains the dye composition as defined above, and a second compartment of which contains the oxidizing composition as defined above. These devices can be equipped with a means for applying the desired mixture to the hair, such as the devices described in patent FR-2 586 913 in the name of the Applicant.
The examples which follow are intended to illustrate the invention without, however, limiting its scope.